CVE-2025-58839 Overview
CVE-2025-58839 is a PHP Object Injection vulnerability in the aThemeArt eDS Responsive Menu plugin for WordPress. The flaw stems from deserialization of untrusted data [CWE-502] and affects all plugin versions up to and including 1.2. An authenticated attacker with high privileges can submit crafted serialized payloads that the plugin passes to unserialize(), triggering PHP object instantiation. When suitable magic methods exist in the application or other loaded plugins, this primitive can be chained into remote code execution, file manipulation, or data tampering.
Critical Impact
Successful exploitation enables object injection in WordPress sites running eDS Responsive Menu ≤ 1.2, with potential for full site compromise via POP chain gadgets.
Affected Products
- aThemeArt eDS Responsive Menu plugin for WordPress
- All versions from n/a through 1.2
- WordPress sites with the eds-responsive-menu plugin installed and active
Discovery Timeline
- 2025-09-05 - CVE-2025-58839 published to the National Vulnerability Database
- 2026-04-23 - Last updated in NVD database
Technical Details for CVE-2025-58839
Vulnerability Analysis
The vulnerability is classified as Insecure Deserialization (Object Injection) under [CWE-502]. The eDS Responsive Menu plugin accepts attacker-controlled input that is subsequently passed to PHP's unserialize() function without prior validation or integrity checks.
PHP object injection allows attackers to instantiate arbitrary classes available in the runtime. By itself, instantiation is harmless. However, when classes implement magic methods such as __wakeup(), __destruct(), or __toString(), attackers can construct property chains (POP chains) that execute attacker-controlled logic. WordPress environments often load many plugins and themes, expanding the gadget surface significantly.
The attack requires high-privilege authentication, meaning the attacker must already control an administrative or equivalent account. This constraint reduces drive-by exploitation risk but remains relevant in multi-admin sites, supply-chain scenarios, and post-credential-theft attacks.
Root Cause
The plugin fails to validate or sanitize serialized data before passing it to unserialize(). PHP serialization is not designed as a security boundary. Any deserialization of untrusted input creates an object injection primitive whose impact depends on classes loaded in the request context.
Attack Vector
The attack vector is network-based and requires authentication. An attacker submits a crafted serialized payload through a plugin endpoint or stored configuration field. When the plugin deserializes the payload, PHP instantiates the embedded classes and triggers their magic methods. The vulnerability mechanism is described in the Patchstack WordPress Plugin Vulnerability advisory.
No public proof-of-concept exploit code has been released for this CVE.
Detection Methods for CVE-2025-58839
Indicators of Compromise
- HTTP POST requests to eds-responsive-menu plugin endpoints containing serialized PHP payloads starting with O:, a:, or s: patterns
- Unexpected new administrative users, modified WordPress options, or webshells dropped under wp-content/
- PHP error log entries referencing __wakeup, __destruct, or unknown class names triggered from plugin request handlers
Detection Strategies
- Inspect web application firewall (WAF) and reverse-proxy logs for request bodies or parameters containing PHP serialization markers targeting plugin URLs
- Monitor WordPress audit logs for changes to options, users, or plugin files made by accounts immediately after submitting plugin configuration data
- Compare installed plugin version against the fixed release across all managed WordPress sites
Monitoring Recommendations
- Forward WordPress and PHP-FPM logs to a centralized SIEM and alert on unserialize() warnings and unexpected class instantiation
- Baseline outbound network connections from PHP processes and alert on new destinations, which often indicate post-exploitation command-and-control
- Track file integrity for wp-content/plugins/eds-responsive-menu/ and the WordPress root
How to Mitigate CVE-2025-58839
Immediate Actions Required
- Update the eDS Responsive Menu plugin to a patched release once published by aThemeArt, or deactivate and remove the plugin if no fix is available
- Audit administrative accounts and rotate credentials for any privileged user who may have submitted untrusted serialized data
- Review WordPress core, plugin, and theme files for unauthorized modifications and remove any unknown PHP files
Patch Information
Refer to the Patchstack advisory for eDS Responsive Menu for current patch status. At the time of NVD publication, affected versions extended through 1.2 with no fixed version listed.
Workarounds
- Deactivate and uninstall the eDS Responsive Menu plugin until a vendor patch is released
- Restrict administrative access using IP allowlisting, multi-factor authentication, and the principle of least privilege
- Deploy a WordPress-aware WAF ruleset that blocks PHP serialization patterns in request bodies targeting plugin endpoints
# Disable the vulnerable plugin via WP-CLI until a patch is available
wp plugin deactivate eds-responsive-menu
wp plugin delete eds-responsive-menu
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
